一株亚硝酸盐降解真菌Aspergillus parasiticus JFS的筛选及鉴定

Screening and identification of the nitrite-degrading Aspergillus parasiticus JFS

摘要:

【目的】筛选可降解亚硝酸盐的菌株。【方法】利用亚硝酸盐选择培养基从水样、土样、朽木等20多个样品中筛选目的菌株。利用盐酸萘乙二胺法检测目的菌株在亚硝酸盐液体培养基中降解亚硝酸盐的能力，利用镉柱还原法和试纸法鉴定亚硝酸盐被目的菌株代谢后的产物；利用菌落形态、菌丝及分生孢子形态、ITS DNA序列、β-Tubulin gene序列及Calmodulin gene序列分析等鉴定目的菌株。【结果】得到一株可强烈降解亚硝酸盐的真菌菌株JFS，其能在亚硝酸盐浓度高达20.0 g/L的液体培养基中很好的生长，菌株JFS将亚硝酸盐降解为无毒的硝酸盐和铵根离子。结合形态学、对培养基的要求及上述3个基因序列的进化树分析，该菌株属于寄生曲霉菌(Aspergillus parasiticus)。【结论】菌株JFS具有强烈的降解亚硝酸盐的能力。

Abstract:

[Objective] Our purpose is to screen the strains that degrade the nitrite. [Methods] We screened the target strains on plate with nitrite selective medium from more than 20 samples such as water, soil and deadwood. We tested the ability of the target strains degrades nitrite by the method of hydrochloric acid naphthalene ethylenediamine. Cadmium column reduction method and test paper method were used to detect the metabolic product of nitrite in the strains. We identified the target strains by morphological characteristics, hyphal and conidial morphology and homology of ITS rDNA sequence and β-Tubulin gene sequence and Calmodulin gene sequence. [Results] We obtained a biodegradable nitrite strains JFS. The strains JFS has a strong ability to degrade nitrite and degrade nitrite to non-toxic nitrate and NH4+. Even concentration of nitrite up to 20% in medium, it also grows very well. According to the morphology, the requirement to culture medium, the 3 gene sequences and phylogenetic studies, the strains JFS belongs to the Aspergillus parasiticus. We identified it as Aspergillus parasiticus. [Conclusion] The strains JFS has a strong ability to degrade nitrite.